ACP-204 in Adults With Alzheimer's Disease Psychosis

A Master Protocol for Three Independent, Seamlessly Enrolling, Double-blind, Placebo-controlled Efficacy and Safety Studies of ACP-204 in Adults With Alzheimer's Disease Psychosis

This is a master protocol for 3 independent, seamlessly enrolling, multicenter, randomized, double-blind, placebo-controlled, parallel-group studies in patients with ADP

• Substudy 1 (Phase 2) will evaluate efficacy and dose response of ACP-204 30 and 60 mg vs placebo. This substudy will be initiated first.
• Substudies 2A and 2B (both: Phase 3) will be confirmatory studies of either both doses (ACP-204 30 and 60 mg, respectively) or a single dose from Part 1 vs placebo. Substudies 2A and 2B will be performed independently of each other and will commence after enrollment of Part 1.

All 3 substudies will be analyzed independently of each other.

Each substudy individually will consist of a screening period (up to 49 days); a double-blind treatment period (6 weeks); a safety follow-up period (30 days) for patients not rolling over into an open-label extension study; and vital status follow-up (for patients who terminated their substudy early).

Study Overview

• Status: Recruiting
• Conditions: Alzheimer's Disease Psychosis
• Intervention / Treatment: Drug: ACP-204; Drug: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 1074
• Phase: Phase 2; Phase 3

Contacts and Locations

• Study Contact: Name: Christine Murphy; Phone Number: 858-465-7480; Email: cmurphy@acadia-pharm.com
• Study Contact Backup: Name: Kristen White; Phone Number: 813-838-6468; Email: kristen.white@acadia-pharm.com

Study Locations

• Brazil
  • Brasília, Brazil, 70840-901
    • Recruiting
    • Hospital Universitario de Brasilia
  • Brasília, Brazil, 70200-730
    • Recruiting
    • L2IP - Instituto de Pesquisas Clínicas Ltda
  • Curitiba, Brazil, 81210-310
    • Recruiting
    • Inst. de Neurologia de Curitiba Hospital Ecoville
  • Curitiba, Brazil, 80240-280
    • Recruiting
    • TrialTech Tecnologia com Pesquisas em Medicamentos
  • Curitiba, Brazil, 80030-310
    • Recruiting
    • CECPAR Centro de Estudos Clinicos do Parana
  • Passo Fundo, Brazil, 99010-120
    • Recruiting
    • Instituto Mederi de Pesquisa e Saude
  • Porto Alegre, Brazil, 90035-001
    • Recruiting
    • Hospital Moinhos de Vento
  • Porto Alegre, Brazil, 90430-001
    • Withdrawn
    • Núcleo de Pesquisa Clínica do Rio Grande do Sul
  • Rio de Janeiro, Brazil, 22270-060
    • Recruiting
    • Ruschel Medicina e Pesquisa Clínica
  • São Bernardo do Campo, Brazil, 09726-150
    • Recruiting
    • Facili-Centro Integrado de Psiquiatria
  • São Paulo, Brazil, 04024-002
    • Recruiting
    • Hospital São Paulo
  • São Paulo, Brazil, 01236-030
    • Recruiting
    • BR Trials-Ensaios Clinicos e Consultoria
  • São Paulo, Brazil, 05403-000
    • Withdrawn
    • Hospital das Clínicas da Faculdade de Medicina USP
  • São Paulo, Brazil, 04550-000
    • Recruiting
    • Santa Paula Hospital Clinical Research Center
• Bulgaria
  • Cherven Bryag, Bulgaria, 5980
    • Recruiting
    • ET Dr. Ivo Natsov - AIPSMC in Psychiatry
  • Kardzhali, Bulgaria, 6600
    • Recruiting
    • Medical Center Lifemed
  • Pazardzhik, Bulgaria, 4400
    • Recruiting
    • DCC "Higia"
  • Pleven, Bulgaria, 5800
    • Recruiting
    • Medical center Medconsult Pleven OOD
  • Plovdiv, Bulgaria, 4004
    • Withdrawn
    • Medical center Spectar-Plovdic EOOD
  • Plovdiv, Bulgaria, 4000
    • Recruiting
    • UMHAT Sv. Georgi EAD
  • Sofia, Bulgaria, 1408
    • Recruiting
    • DCC St. Vrach and St. St. Kuzma and Damian OOD
  • Sofia, Bulgaria, 1431
    • Recruiting
    • UMHAT "Alexandrovska" EAD
  • Sofia, Bulgaria, 1431
    • Recruiting
    • UMHAT Alexandrovska EAD
  • Sofia, Bulgaria, 1377
    • Recruiting
    • Mental Health Centre - Prof. N Shipkovenski EOOD
  • Sofia, Bulgaria, 1680
    • Withdrawn
    • Medical Center Intermediea
  • Sofia, Bulgaria, 1510
    • Withdrawn
    • Medical Center Hera EOOD
  • Stara Zagora, Bulgaria, 6003
    • Withdrawn
    • UMHAT Prof. Dr. St. Kirkovich AD
• Chile
  • Antofagasta, Chile, 1270244
    • Recruiting
    • Psicomed Estudios Medicos
  • Santiago, Chile, 7500710
    • Recruiting
    • BioMedica Research Group
  • Santiago, Chile, 7560356
    • Recruiting
    • Especialidades Medicas L Y S
  • Santiago, Chile, 8330024
    • Recruiting
    • CIC de la Universidad Catolica CICUC
• Czechia
  • Brno, Czechia, 656 91
    • Recruiting
    • Fakultni nemocnice u sv. Anny v Brne
  • Choceň, Czechia, 56501
    • Recruiting
    • NEUROHK s.r.o
  • Prague, Czechia, 100 00
    • Recruiting
    • CLINTRIAL s.r.o.
  • Prague, Czechia, 186 00
    • Withdrawn
    • INEP medical s.r.o
  • Prague, Czechia, 160 00
    • Withdrawn
    • FORBELI s.r.o.
  • Rychnov nad Kněžnou, Czechia, 516 01
    • Recruiting
    • Vestra Clinics s.r.o.
  • Czech Republic
    • Kladno, Czech Republic, Czechia, 27201
      • Recruiting
      • BRAIN-SOUL THERAPY s.r.o.
    • Prague, Czech Republic, Czechia, 109 00
      • Recruiting
      • Ad71 S.R.O.
• France
  • Bron, France, 69677
    • Withdrawn
    • Hopital Neurologique Bron
  • Colmar, France, 68000
    • Withdrawn
    • Centre pour Personnes Âgées
  • Dijon, France, 21000
    • Recruiting
    • Centre Memoire Ressources Recherche CMRR
  • Limoges, France, 87042
    • Recruiting
    • CHU de Limoges-Hopital Dupuytren
  • Lyon, France, 69002
    • Withdrawn
    • Hospices Civils de Lyon HCL
  • Paris, France, 75010
    • Recruiting
    • Hôpital Lariboisière
  • Paris, France, 75013
    • Recruiting
    • Hopital Broca
  • Rouen, France, 76031
    • Recruiting
    • CHU Rouen-Hospital Charles Nicolle
  • Toulouse, France, 31059
    • Recruiting
    • Hôpital La Grave
  • Toulouse, France, 31059
    • Withdrawn
    • Hopital Purpan
  • Tours, France, 37044
    • Recruiting
    • CHRU de Tours- Hopital Bretonneau
  • Vandœuvre-lès-Nancy, France, 545000
    • Recruiting
    • Hôpital de Brabois Adultes
• Italy
  • Brescia, Italy, 25123
    • Recruiting
    • Asst Degli Spedali Civili Di Brescia
  • Cefalù, Italy, 90015
    • Recruiting
    • Neurologia-Fondazione Instituto G. Giglio
  • Isernia, Italy, 86077
    • Withdrawn
    • IRCCS Neuromed Istituto Neurologico Mediterraneo
  • Milan, Italy, 20132
    • Withdrawn
    • Ospedale San Raffaele
  • Roma, Italy, 00168
    • Recruiting
    • Policlinico Universitario Agostino Gemelli
  • Roma, Italy, 00128
    • Recruiting
    • Fondazione Policlinico Uni Campus Bio-Medico di Roma
  • Roma, Italy, 00185
    • Withdrawn
    • AOU Policlinico Umberto I
  • Salerno, Italy, 84131
    • Recruiting
    • Azienda Ospedaliera Universitaria OO. RR. S.
  • Torino, Italy, 10126
    • Withdrawn
    • Dipartimento di Neuroscienze Rita Levi Montalcini
  • Tricase, Italy, 73039
    • Recruiting
    • Azienda Ospedaliera Card. G. Panico
• Mexico
  • Coahuila, Mexico, 25000
    • Recruiting
    • Hospital Universitario Dr. Gonzalo Valdes Valdes
  • Estado de México, Mexico, 54055
    • Recruiting
    • Clinical Research Institute S.C
  • Mazatlán, Mexico, 82140
    • Recruiting
    • B&B Investigaciones Medicas SC
  • Mexico City, Mexico, 03100
    • Recruiting
    • Mexico Centre for Clinical Research S.A de C.V
  • Mexico City, Mexico, 03100
    • Recruiting
    • Health Pharma Professional Research S.A. de C.V.
  • Nuevo León, Mexico, 64620
    • Recruiting
    • Centro Estudios Clínicos y Esp. Médicas SC CECEM
  • San Luis Potosí City, Mexico, 78213
    • Recruiting
    • BIND Investigaciones S.C.
  • Sinaloa, Mexico, 80230
    • Recruiting
    • Centro para el Des de la Med y de Asist Med Esp SC
  • Sinaloa, Mexico, 80020
    • Recruiting
    • Neurociencias Estudios Clinicos
  • N.L
    • Monterrey, N.L, Mexico, 64310
      • Recruiting
      • Iecsi S.C.
  • Nuevo León
    • Monterrey, Nuevo León, Mexico, 64460
      • Recruiting
      • Hospital Universitario Dr. Jose Eleuterio González
• Serbia
  • Belgrade, Serbia, 11000
    • Recruiting
    • Institute of Mental Health
  • Belgrade, Serbia, 11000
    • Recruiting
    • Special Hospital for Cerebrovascular Disease Sveti Sava
  • Belgrade, Serbia, 11000
    • Recruiting
    • Clinical. Hospital Center Zvezdara
  • Belgrade, Serbia, 11000
    • Recruiting
    • Clinical Hosp Center Dr Dragisa Misovic Dedinje
  • Gornja Toponica, Serbia, 18202
    • Recruiting
    • Special Hospital for Psychiatric Diseases
  • Kovin, Serbia, 26220
    • Withdrawn
    • Spl. Hosp. for Psychiatric Diseases Kovin
  • Kragujevac, Serbia, 34000
    • Recruiting
    • University Clinical Center Kragujevac
  • Kragujevac, Serbia, 34000
    • Recruiting
    • Jovanovic University Clinical Centre of Kragujevac
  • Kragujevac, Serbia, 34000
    • Recruiting
    • Janjic University Clinical Center Kragujevac
  • Niš, Serbia, 18000
    • Recruiting
    • University Clinical Center Niš
  • Novi Kneževac, Serbia, 23330
    • Withdrawn
    • Spl. Hosp. for Psychiatric Diseases Sveti Vracevi
  • Sombor, Serbia, 25000
    • Withdrawn
    • Gen. Hosp. Dr Radivoj Simonovic
  • Valjevo, Serbia, 14000
    • Withdrawn
    • General Hospital Valjevo
• South Korea
  • Incheon, South Korea, 21565
    • Recruiting
    • Gachon University Gil Medical Center
  • Incheon, South Korea, 22332
    • Recruiting
    • Inha University Hospital
  • Seoul, South Korea, 06351
    • Recruiting
    • Samsung Medical Center
  • Seoul, South Korea, 02841
    • Recruiting
    • Korea University Anam Hospital
  • Seoul, South Korea, 03312
    • Recruiting
    • Eunpyeong St. Mary's Hospital
  • Seoul, South Korea, 07061
    • Recruiting
    • SMG-SNU Boramae Medical Center
  • Seoul, South Korea, 04763
    • Withdrawn
    • Hanyang University Seoul Hospital
  • Seoul, South Korea, 05030
    • Withdrawn
    • Konkuk University Medical Center
• Spain
  • Seville, Spain, 41009
    • Recruiting
    • Hospital Universitario Virgen Macarena
  • Zamora, Spain, 49021
    • Recruiting
    • Hospital Provincial de Zamora
• Taiwan
  • Kaohsiung City, Taiwan, 80756
    • Recruiting
    • Kaohsiung Medical University Chung-Ho Memorial Hospital
  • Kaohsiung City, Taiwan
    • Recruiting
    • E-DA Hospital
  • New Taipei City, Taiwan, 23561
    • Withdrawn
    • Taipei Medical University-Shuang Ho Hospital
  • Tainan, Taiwan, 704
    • Recruiting
    • National Cheng Kung University Hospital
  • Taipei, Taiwan, 10002
    • Recruiting
    • National Taiwan University Hospital
• United States
  • Arizona
    • Chandler, Arizona, United States, 85224
      • Recruiting
      • Chandler Clinical Trials
    • Scottsdale, Arizona, United States, 85258
      • Recruiting
      • Clinical Endpoint LLC
  • California
    • Anaheim, California, United States, 92805
      • Withdrawn
      • Advanced Research Center, Inc.
    • Costa Mesa, California, United States, 92626
      • Recruiting
      • ATP Clinical Research
    • Fresno, California, United States, 93710
      • Recruiting
      • Neuro-Pain Medical Center
    • Garden Grove, California, United States, 92844
      • Withdrawn
      • National Institute Of Clinical Research
  • Florida
    • Aventura, Florida, United States, 33180
      • Recruiting
      • Humanity Clinical Research Corp
    • Daytona Beach, Florida, United States, 32117
      • Recruiting
      • Arrow Clinical Trials
    • Doral, Florida, United States, 33178
      • Recruiting
      • First Excellent Research Group
    • Hialeah, Florida, United States, 33012
      • Recruiting
      • New Life Medical Research Center Inc.
    • Hialeah, Florida, United States, 33012
      • Recruiting
      • Reliable Clinical Research LLC.
    • Miami, Florida, United States, 33176
      • Withdrawn
      • Visionary Investigators Network
    • Miami, Florida, United States, 33122
      • Recruiting
      • Premier Clinical Research Institute, Inc.
    • Miami, Florida, United States, 33165
      • Recruiting
      • MediClear Medical & Research Center, Inc.
    • Miami, Florida, United States, 33032
      • Recruiting
      • Homestead Associates in Research Inc.
    • Miami, Florida, United States, 33165
      • Recruiting
      • Future Care Solution, LLC
    • Miami, Florida, United States, 33135
      • Recruiting
      • Verus Clinical Research
    • Miami, Florida, United States, 33135
      • Recruiting
      • Advanced Clinical Research Network, Corp
    • Miami, Florida, United States, 33125
      • Withdrawn
      • Central Miami Medical Institute
    • Miami, Florida, United States, 33176
      • Recruiting
      • ABBA Medical Group LLC
    • Miami Beach, Florida, United States, 33140
      • Recruiting
      • Quantum Clinical Trials
    • Miami Gardens, Florida, United States, 33056
      • Recruiting
      • New Med Research
    • Miami Lakes, Florida, United States, 33016
      • Recruiting
      • Floridian Neuroscience Institutue
    • Orlando, Florida, United States, 32807
      • Recruiting
      • Combined Research Orlando Phase I IV
    • Tampa, Florida, United States, 33614
      • Withdrawn
      • Psych Me Medical Research Inc
    • West Palm Beach, Florida, United States, 33407
      • Recruiting
      • Neuroscience Research Institute
  • Illinois
    • Elgin, Illinois, United States, 60123
      • Withdrawn
      • Revive Research Institute, Inc.
  • Louisiana
    • Shreveport, Louisiana, United States, 71105
      • Recruiting
      • Grace Research, LLC
  • Michigan
    • Rochester Hills, Michigan, United States, 48307
      • Withdrawn
      • Khan Revive Research Institute
  • Nebraska
    • Lincoln, Nebraska, United States, 68526
      • Withdrawn
      • Alivation Research, LLC
  • New York
    • Amherst, New York, United States, 14226
      • Withdrawn
      • Dent Neurologic Institute
    • Rochester, New York, United States, 14618
      • Withdrawn
      • Finger Lakes Clinical Research
    • The Bronx, New York, United States, 10466
      • Withdrawn
      • Regional Neurological Associates
  • Ohio
    • Beachwood, Ohio, United States, 44122
      • Withdrawn
      • Insight Clinical Trials Llc
    • Centerville, Ohio, United States, 45459
      • Withdrawn
      • Valley Medical Research
  • Pennsylvania
    • Abington, Pennsylvania, United States, 19001
      • Recruiting
      • Abington Neurological Associates
  • Texas
    • Cypress, Texas, United States, 77429
      • Recruiting
      • Horizon Clinical Research Group
    • Houston, Texas, United States, 77074
      • Recruiting
      • Clinical Trial Network LLC
    • Houston, Texas, United States, 77089
      • Recruiting
      • Kaleidoscope Clinical Research
    • Houston, Texas, United States, 77054
      • Recruiting
      • University of Texas Health Science Center
    • Houston, Texas, United States, 77054
      • Recruiting
      • Prolato Clinical Research Center-Patton
    • Houston, Texas, United States, 77089
      • Recruiting
      • Steven South Goldstein MD and Associates
    • Pasadena, Texas, United States, 77504
      • Recruiting
      • World Research Link
    • Stafford, Texas, United States, 77477
      • Withdrawn
      • R & H Clinical Research Inc.
    • Webster, Texas, United States, 77598
      • Withdrawn
      • Tranquil Clinical Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Is male or female and ≥55 and ≤95 years of age living in the community or in an institutionalized setting
• Meets clinical criteria for possible or probable AD based on the 2011 National Institute on Aging-Alzheimer Association (NIA-AA) criteria
• Meets the revised criteria for psychosis in major or mild neurocognitive disorder established by the International Psychogeriatrics Association (IPA)
• Has either blood-based biomarker or documented evidence (e.g. positron emission tomography, cerebrospinal fluid biomarker) indicating amyloid plaque deposition and neuropathologic change consistent with AD
• Has a prior magnetic resonance imaging or computed tomography scan of the brain that is consistent with the diagnosis of AD
• Meets revised criteria for psychosis in major or mild neurocognitive disorder as per International Psychogeriatrics Association
• MMSE score ≥6 and ≤24
• Psychotic symptoms for at least 2 months
• Lives in a stable place of residence and there are no plans to change living arrangements
• Has a designated study partner/caregiver
• Able to complete all study visits with a study partner/caregiver
• Must be on a stable dose of cholinesterase inhibitor or memantine, if applicable

Exclusion Criteria:

• Requires treatment with a medication prohibited by the protocol
• Is in hospice and receiving end-of-life palliative care, or has become bedridden
• Requires skilled nursing care
• Psychotic symptoms that are primarily attributable to delirium, substance abuse, or a medical or psychiatric condition other than dementia
• Known history of cerebral amyloid angiopathy, epilepsy, central nervous system neoplasm, or unexplained syncope
• Atrial fibrillation
• Symptomatic orthostatic hypotension
• Protocol-defined exclusionary clinical laboratory findings
• Treatment with anti-tau therapy or donanemab within 2 months prior to Screening

Additional inclusion/exclusion criteria apply. Subjects will be evaluated at screening to ensure that all criteria for study participation are met.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ACP-204 30 mg; Administration once daily at approximately the same time of day, with or without food	Drug: ACP-204; ACP-204 is a potent and selective antagonist/inverse agonist of 5-hydroxytryptamine (serotonin) receptor subtype 2A.
Experimental: ACP-204 60 mg; Administration once daily at approximately the same time of day, with or without food	Drug: ACP-204; ACP-204 is a potent and selective antagonist/inverse agonist of 5-hydroxytryptamine (serotonin) receptor subtype 2A.
Placebo Comparator: Placebo; Administration once daily at approximately the same time of day, with or without food	Drug: Placebo; ACP-204 matching placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Scale for the Assessment of Positive Symptoms-Hallucinations and Delusions subscales (SAPS-H+D) total score change from baseline (Substudies 1, 2A, 2B)	The SAPS-H+D subscales are a measure of two psychotic symptoms: hallucinations and delusions. The SAPS-H+D total score is the sum of the scores of the Hallucinations and Delusions subscales. The hallucinations domain score (SAPS-H) is the sum of the 7 hallucinations item scores, and the delusions domain core (SAPS-D) is the sum of the 13 delusions item scores.	From baseline to Week 6

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical Global Impression-Improvement in the ADP context (CGI-I-ADP) score	The CGI-I scale is a clinician-rated, 7-point scale used to rate the improvement in symptoms at the time of assessment, relative to the symptoms at Baseline. The CGI-I-ADP scale is the CGI-I scale applied in the ADP context, in which hallucinations and delusions are the symptoms of interest.	Week 6

Collaborators and Investigators

• Sponsor: ACADIA Pharmaceuticals Inc.

Study record dates

Study Major Dates

• Study Start (Actual): November 14, 2023
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): February 1, 2028

Study Registration Dates

• First Submitted: November 27, 2023
• First Submitted That Met QC Criteria: November 27, 2023
• First Posted (Actual): December 7, 2023

Study Record Updates

• Last Update Posted (Actual): May 27, 2026
• Last Update Submitted That Met QC Criteria: May 22, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Delusions; Hallucinations; Alzheimer's disease psychosis
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Behavioral Symptoms; Neurobehavioral Manifestations; Perceptual Disorders; Pathological Conditions, Signs and Symptoms; Behavior; Signs and Symptoms; Hallucinations; Delusions; Substandard Drugs; Pharmaceutical Preparations; Counterfeit Drugs
• Other Study ID Numbers: ACP-204-006

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No